From: Linus Torvalds torvalds@linux-foundation.org
[ Upstream commit efbcbb12ee99f750c9f25c873b55ad774871de2a ]
The __find_restype() function loops over the m5mols_default_ffmt[] array, and the termination condition ends up being wrong: instead of stopping when the iterator becomes the size of the array it traverses, it stops after it has already overshot the array.
Now, in practice this doesn't likely matter, because the code will always find the entry it looks for, and will thus return early and never hit that last extra iteration.
But it turns out that clang will unroll the loop fully, because it has only two iterations (well, three due to the off-by-one bug), and then clang will end up just giving up in the middle of the loop unrolling when it notices that the code walks past the end of the array.
And that made 'objtool' very unhappy indeed, because the generated code just falls off the edge of the universe, and ends up falling through to the next function, causing this warning:
drivers/media/i2c/m5mols/m5mols.o: warning: objtool: m5mols_set_fmt() falls through to next function m5mols_get_frame_desc()
Fix the loop ending condition.
Reported-by: Jens Axboe axboe@kernel.dk Analyzed-by: Miguel Ojeda miguel.ojeda.sandonis@gmail.com Analyzed-by: Nick Desaulniers ndesaulniers@google.com Link: https://lore.kernel.org/linux-block/CAHk-=wgTSdKYbmB1JYM5vmHMcD9J9UZr0mn7BOY... Fixes: bc125106f8af ("[media] Add support for M-5MOLS 8 Mega Pixel camera ISP") Cc: HeungJun, Kim riverful.kim@samsung.com Cc: Sylwester Nawrocki s.nawrocki@samsung.com Cc: Kyungmin Park kyungmin.park@samsung.com Cc: Mauro Carvalho Chehab mchehab@redhat.com Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/i2c/m5mols/m5mols_core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/media/i2c/m5mols/m5mols_core.c b/drivers/media/i2c/m5mols/m5mols_core.c index 21666d705e372..dcf9e4d4ee6b8 100644 --- a/drivers/media/i2c/m5mols/m5mols_core.c +++ b/drivers/media/i2c/m5mols/m5mols_core.c @@ -488,7 +488,7 @@ static enum m5mols_restype __find_restype(u32 code) do { if (code == m5mols_default_ffmt[type].code) return type; - } while (type++ != SIZE_DEFAULT_FFMT); + } while (++type != SIZE_DEFAULT_FFMT);
return 0; }